A few days after Marceline was claimed as Child of Hades, she had always wanted to see her father and ask him a few things. One morning, she was awaken by a barking of a dog. She got up un saw the ghost dog. Around her neck, there is a skull necklase and a letter hanging. She touched the letter. It floated infront of her and it red:

Dear Marceline,

Accept this ghost dog as a gift from me. Sorry I've never visited you and that you had never seen me. Your mother hated me when she found out who I really am.

With love from your father,

Hades

The dog has grey spots so she called her "Greyson" and she shared her with her other siblings.

5. Any special abilities: As a ghost dog, it can float, passes and deosn't bump into things,can shadow travel and can only be handled by children of Hades and Melinoe